Zac Blobs are still creep blocking.
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This has been an issue for quite some time now. Occasionally the blobs that Zac drops from his passive will block you like a minion. It hasn't been too apparent until this most recent patch where I am now experiencing this at least two to four times a game. You can clearly see that the blob is even blocking the path of the minions as they path around the blob as well, this is a HUGE issue especially for Zac top.